Multi-port delivery system

ABSTRACT

A device for delivering material to multiple surgical target locations includes a pressure reservoir selectably coupled to two or more outlets. Coupling the pressure reservoir to a given one of the outlets and pressurizing the pressure reservoir causes flowable material (e.g., bone filler material) to be dispensed from that outlet. A diverter for selectably coupling the pressure reservoir one of the outlets can be configured to trigger a pressure release valve for the pressure reservoir upon switching, thereby preventing unexpected or uncontrolled material delivery from the new outlet in response to sudden high pressure exposure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 12/771,812,filed on Apr. 30, 2010, the contents of which are herein incorporated byreference in their entirety.

FIELD OF THE INVENTION

The invention relates to a system and method for performing a surgicalprocedure, and in particular, to a pressure delivery device thatprovides multiple output ports in a single instrument.

BACKGROUND OF THE INVENTION

A minimally invasive procedure is a medical procedure that is performedthrough the skin or an anatomical opening. In contrast to an openprocedure for the same purpose, a minimally invasive procedure willgenerally be less traumatic to the patient and result in a reducedrecovery period.

However, there are numerous challenges that minimally invasiveprocedures present. For example, minimally invasive procedures aretypically more time-consuming than their open procedure analogues due tothe challenges of working within a constrained operative pathway. Inaddition, without direct visual feedback into the operative location,accurately selecting, sizing, placing, and/or applying minimallyinvasive surgical instruments and/or treatment materials/devices can bedifficult.

For example, for many individuals in our aging world population,undiagnosed and/or untreatable bone strength losses have weakened theseindividuals' bones to a point that even normal daily activities pose asignificant threat of fracture. In one common scenario, when the bonesof the spine are sufficiently weakened, the compressive forces in thespine can cause fracture and/or deformation of the vertebral bodies. Forsufficiently weakened bone, even normal daily activities like walkingdown steps or carrying groceries can cause a collapse of one or morespinal bones. A fracture of the vertebral body in this manner istypically referred to as a vertebral compression fracture. Othercommonly occurring fractures resulting from weakened bones can includehip, wrist, knee and ankle fractures, to name a few.

Fractures such as vertebral compression fractures often result inepisodes of pain that are chronic and intense. Aside from the paincaused by the fracture itself, the involvement of the spinal column canresult in pinched and/or damaged nerves, causing paralysis, loss offunction, and intense pain which radiates throughout the patient's body.Even where nerves are not affected, however, the intense pain associatedwith all types of fractures is debilitating, resulting in a great dealof stress, impaired mobility and other long-term consequences. Forexample, progressive spinal fractures can, over time, cause seriousdeformation of the spine (“kyphosis”), giving an individual ahunched-back appearance, and can also result in significantly reducedlung capacity and increased mortality.

Because patients with these problems are typically older, and oftensuffer from various other significant health complications, many ofthese individuals are unable to tolerate invasive surgery. Therefore, inan effort to more effectively and directly treat vertebral compressionfractures, minimally invasive techniques such as vertebroplasty and,subsequently, kyphoplasty, have been developed. Vertebroplasty involvesthe injection of a flowable reinforcing material, usuallypolymethylmethacrylate (PMMA—commonly known as bone cement), into afractured, weakened, or diseased vertebral body. Shortly afterinjection, the liquid filling material hardens or polymerizes, desirablysupporting the vertebral body internally, alleviating pain andpreventing further collapse of the injected vertebral body.

Because the liquid bone cement naturally follows the path of leastresistance within bone, and because the small-diameter needles used todeliver bone cement in vertebroplasty procedure require either highdelivery pressures and/or less viscous bone cements, ensuring that thebone cement remains within the already compromised vertebral body is asignificant concern in vertebroplasty procedures. Kyphoplasty addressesthis issue by first creating a cavity within the vertebral body (e.g.,with an inflatable balloon) and then filling that cavity with bonefiller material. The cavity provides a natural containment region thatminimizes the risk of bone filler material escape from the vertebralbody. An additional benefit of kyphoplasty is that the creation of thecavity can also restore the original height of the vertebral body,further enhancing the benefit of the procedure.

Typically, kyphoplasty is performed using a bilateral procedure, inwhich access to the interior of the vertebral body is achieved viapedicular access. Cavities are created in both the left and right halvesof the vertebral body interior, and subsequently filled with bone fillermaterial. This bilateral approach can often create a more stable supportstructure than would be possible using only a unipedicular approach, andcan also enhance vertebral body height restoration and maintenance.

However, because conventional cement delivery systems provide only asingle delivery output, filling the two cavities can be a cumbersometask. A separate cement delivery system could be used for each cavity,or a single cement delivery system must be moved between the two accesscannulas. In either case, the logistics of performing the cementdelivery are less than ideal, as the physician performing the procedureis forced to either interact with two separate delivery devices orphysically transport a single delivery device between cannulas.

Accordingly, it is desirable to provide surgical tools and techniquesthat enable user-friendly material delivery during surgical procedures.

SUMMARY OF THE INVENTION

By incorporating a diverter element into a pump with multiple outputs, amaterial delivery system can service multiple surgical target locationsfrom a single control point.

In various embodiments, a material delivery system can include apressure reservoir, a pressure source for pressurizing the pressurereservoir, and a diverter for selectably coupling the pressure reservoirto one of multiple outputs. In some embodiments, the pressure reservoircan include a pressure release valve for venting the pressure reservoirto a predetermined baseline pressure (e.g., ambient/atmosphericpressure). The diverter can be configured to trigger (open) the pressurerelease valve whenever switching between different outputs.Alternatively, the diverter can itself vent the pressure reservoirduring switching (e.g., by creating a flow path from the pressurereservoir to the baseline pressure). By automatically venting during theswitching process, unintended and/or uncontrolled material delivery canbe prevented when the pressure reservoir is initially coupled to the newoutput. In various embodiments, this vent triggering can occur while oneor both of the original and destination outputs are coupled to thepressure reservoir.

In various embodiments, the pressure reservoir can contain a hydraulicfluid that transmits the pressure within the pressure reservoir to aremote material dispensing element (e.g., via hydraulic lines/flexibletubing). The material dispending element then dispenses the actualflowable material (e.g., bone filler material) in response to thepressure transmitted via the hydraulic fluid. In various otherembodiments, the pressure reservoir can contain the actual flowablematerial that is expressed from the pressure reservoir through theselected output.

In various embodiments, a surgical procedure (e.g., kyphoplasty) can beperformed using a single material delivery system that includes multipleoutputs selectably coupled to a single pressure reservoir. The flowablematerial can be delivered to each the different surgical targetlocations individually by manually switching between the differentoutputs. In various embodiments, switching between different outputsautomatically vents the pressure reservoir to a baseline pressure. As aresult, sudden high pressure output from the new output can beprevented, thereby minimizing the risk of adverse events during thesurgical procedure (e.g., cement extravasation during kyphoplasty orvertebroplasty).

As will be realized by those of skilled in the art, many differentembodiments of a multi-output material delivery system, along withsystems, kits, and/or methods of using such a material delivery systemare possible. Additional uses, advantages, and features of such amaterial delivery system are set forth in the illustrative embodimentsdiscussed in the detailed description herein and will become moreapparent to those skilled in the art upon examination of the following.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D show an exemplary schematic diagram of a material deliverysystem having multiple selectable outputs.

FIGS. 2A-2F show an exemplary implementation of the multi-outputmaterial delivery system of FIGS. 1A-1D.

FIGS. 3A-3G show an exemplary bilateral kyphoplasty procedure performedusing the multi-output material delivery system of FIGS. 2A-2F.

FIGS. 4A-4C show another exemplary implementation of the multi-outputmaterial delivery system of FIGS. 1A-1D.

FIGS. 5A-5D show another exemplary implementation of the multi-outputmaterial delivery system of FIGS. 1A-1D.

DETAILED DESCRIPTION

By incorporating a diverter element into a material delivery system withmultiple outputs, the material delivery system can service multiplesurgical targets from a single control point.

FIG. 1A is a schematic diagram of a material delivery system 100 thatincludes multiple material dispensing outlets 151. For exemplarypurposes, material delivery system 100 is depicted as having twodispensing outlets 151A and 151B, but in various other embodiments,material delivery system 100 can include any number of dispensingoutlets 151. Material delivery system 100 further includes a pressurereservoir 110, a pressure source 120, a diverter 130, a pressure releasevalve 140, pressure outlets 150A and 1506, and material dispensingelements 155A and 155B.

Pressure source 120 can be any system for pressurizing pressurereservoir 110. In one embodiment, pressure source 120 can be a basichand pump for driving a piston or plunger (e.g., via a squeeze triggeror crank) to pressurize reservoir 110. In various other embodiments,pressure source 120 can be a powered hydraulic pump or prechargedpressure vessel coupled to pressure reservoir 110 by a valve. Any numberof additional alternatives will be readily apparent.

Diverter 130 selectably couples pressure reservoir 110 to one ofpressure outlets 150A and 150B, and therefore to one of materialdispensing elements 155A and 155B, respectively. This pressureapplication causes the recipient material dispensing system 155 toexpress a flowable material from its associated dispensing outlet 151.Note that “flowable material” as described herein can be any materialcapable of being dispensed from material delivery system 100, such asPMMA, granulized or pelletized material such as bone morphongenicprotein (BMP) or graft material, or even solid materials that can beforced from material dispensing elements 155A and 155B (e.g., wax orphase-change materials). In various embodiments, pressure reservoir 110can contain the flowable material itself, such that when diverter 130couples pressure reservoir 110 to, for example, material dispensingelement 155A, the flowable material simply flows from pressure reservoir110 through diverter 130, through material dispensing element 155A, andout of dispensing outlet 151A.

However, in various other embodiments, pressure reservoir 110 cancontain a hydraulic fluid (e.g., water, saline solution, or oil, amongothers) for driving the flowable material from material dispensingelements 155A and 155B. For example, as shown in FIG. 1A, materialdispensing element 155A could include a piston 153A that receiveshydraulic fluid pressure from pressure reservoir 110, and in response tosuch pressure forces flowable material out of material dispensingelement 155A through dispensing outlet 151A.

In various hydraulic fluid-based embodiments of material delivery system100, material dispensing elements 155A and 155B could be coupled topressure outlets 150A and 150B, respectively, by hydraulic lines (e.g.,flexible tubing). This would allow dispensing outlets 151A and 151B tobe positioned more remotely than would be typically be feasible if theactual flowable material were being forced directly from pressurereservoir 110.

In various other embodiments, material delivery system 100 can alsoinclude pressure release valve 140. Pressure release valve 140 is anormally closed valve that, when actuated, vents pressure reservoir 110to a lower pressure region. Typically, the lower pressure region will beat ambient pressure (e.g., atmospheric pressure), but in variousembodiments, the venting can be to a predetermined baseline pressureother than atmospheric pressure. In some embodiments, pressure releasevalve 140 can vent outside of the pressure system (i.e., an open system)as indicated by the solid arrow, and in other embodiments, pressurerelease valve 140 can vent back into the pressure system (i.e., a closedsystem) as indicated by the dotted arrow returning to pressure source120.

When present, pressure release valve 140 can be triggered by the actionof diverter 130. Specifically, switching diverter 130 between outputscan open pressure release valve 140, thereby ensuring that the newlycoupled material dispensing element 155 does not receive a sudden highpressure surge. This automatic pressure “reset” prevents unexpectedand/or uncontrolled material delivery from the newly selected materialdispensing element 155, which can be a critical safety factor during amedical procedure (as described in greater detail below).

For example, in FIG. 1A, diverter 130 is positioned to couple pressurereservoir 110 to material dispensing element 155A. Therefore, aspressure source 120 pressurizes pressure reservoir 110, flowablematerial is dispensed from dispensing outlet 151A. As described above,this dispensing can be due either to either to hydraulic pressuredelivered via a hydraulic fluid in pressure reservoir 110 (e.g., causingpiston 153A to force the flowable material from material dispensingelement 155A), or to the flowable material being driven from pressurereservoir 110 through diverter 130 and through material dispensingelement 155A.

Once a desired amount of flowable material has been expressed fromdispensing outlet 151A, diverter 130 can be switched to a new positionto couple pressure reservoir 110 to material dispensing element 155B. Inone embodiment, as indicated in FIG. 1B, the initiation of thisswitching operation opens pressure release valve 140, thereby ventingpressure reservoir 110. In addition, any residual pressure at materialdispensing element 155A can be eliminated by configuring diverter 130and/or pressure release valve 140 such that pressure release valve 140opens while diverter 130 is still coupling pressure reservoir 110 tomaterial dispensing element 155A. By doing so, material flow fromdispensing outlet 151A can be immediately stopped once switching begins.

In various embodiments, pressure release valve 140 remains open asdiverter 130 couples pressure reservoir 110 to material dispensingelement 155B, as shown in FIG. 1C. In doing so, any pressuredifferential between pressure reservoir 110 and newly connected materialdispensing element 155B can be immediately eliminated without creatingany unintentional discharge of flowable material from dispensing outlet151B.

Note that for exemplary purposes diverter 130 is depicted as creatingdiscrete connections between pressure reservoir 110 and materialdispensing element 155A and between pressure reservoir 110 and materialdispensing element 155B. However, in various other embodiments, diverter130 can exhibit a mode in which pressure reservoir 110 is simultaneouslycoupled to both material dispensing elements 155A and 155B. Openingpressure release valve 140 during such a mode would simultaneouslyequalize pressures at pressure reservoir 110 and material dispensingelements 155A and 155B.

When diverter 130 is fully switched to its new position, pressurerelease valve 140 is closed, as shown in FIG. 1D. Pressure source 120can then be used to pressurize pressure reservoir 110 to dispenseflowable material from material dispensing element 155B, in a mannersubstantially similar to that described with respect to materialdispensing element 155A in FIG. 1A.

FIG. 2A shows an embodiment of material delivery system 100 (describedwith respect to FIGS. 1A-1D) in which diverter 130 is a rotationalelement that defines a flow path 131. In FIG. 2A, flow path 131 ispositioned over an outlet 111 of pressure reservoir 110 and an input topressure outlet 150A. Accordingly, as shown in cross section A-A in FIG.2B, flow path 131 connects pressure reservoir 110 to pressure outlet150A, thereby coupling pressure reservoir 110 to material dispensingelement 155A (depicted by a phantom outline for simplicity's sake) todispense flowable material.

Note that while flow path 131 is depicted as a hollowed-out portion ofdiverter 130 for exemplary purposes, in various other embodiments, flowpath 131 can take any configuration or shape. For example, in variousembodiments, flow path 131 can be a passageway within diverter 130. Notefurther that while diverter 130 is depicted and described as arotational element for exemplary purposes, diverter 130 can exhibit anymode of operation that enables output switching capability. For example,in various embodiments, diverter 130 can be a push-pull element, arotating ball or cylinder valve, or a movable lever, among others.

For exemplary purposes, pressure generator 120 is depicted as a simplepiston 121 that pressurizes pressure reservoir 110 through a one-waycheck valve 122. Such an embodiment is particularly conducive topressure generation in a hand-held device. For example, pressuregenerator 120 can include a trigger 122 that, in response to pressure(e.g., squeezing) by the operator, drives piston 121 inward topressurize pressure reservoir 110.

Likewise, for exemplary purposes, pressure release valve 140 is depictedas a simple one-way check valve with an actuator 142. Note that invarious other embodiments, pressure release valve 140 can incorporateany pressure release mechanism. Raising actuator 142 vents pressurereservoir 110 to ambient pressure (although as described above withrespect to FIGS. 1A-1D, in various other embodiments, pressure releasevalve 140 can be configured to vent to any baseline pressure, either asan open or closed system).

Diverter 130 also includes a triggering feature 132 that is configuredto actuate (open) pressure release valve 140 as diverter 130 is rotated.For exemplary purposes, triggering feature 132 is depicted as a raisedelement on diverter 130 that can slip under actuator 142. Note, however,that in various other embodiments, triggering feature 132 can be anysystem for actuating pressure release valve 140, including a magneticswitch, a proximity sensor, and/or a mechanical linkage.

Thus, as diverter 130 is rotated, as shown in FIG. 2C, triggeringfeature 132 slides under actuator 142, as shown in the cross sectionalview of FIG. 2D. This action opens pressure release valve 140, therebyventing pressure reservoir 110 to a baseline pressure P0 (e.g.,atmospheric pressure). Because flow path 131 still couples pressurereservoir 110 to pressure outlet 150A, the pressure at materialdispensing element 155A is also reduced to baseline pressure P0. Asindicated in FIG. 2C, flow path 131 is sized and shaped to also couplepressure reservoir 110 to pressure outlet 150B during the actuation ofpressure release valve 140, thereby establishing baseline pressure PO atpressure outlet 150B (and hence at material dispensing element 155B,which is not shown for clarity).

Then, as switching is completed as shown in FIG. 2E, triggering feature132 is moved out from under actuator 142, thereby closing pressurerelease valve 140, as shown in cross sectional view A-A in FIG. 2F.Meanwhile, flow path 131 decouples pressure outlet 150A from pressurereservoir 110 (while maintaining the path between pressure reservoir 110and pressure outlet 150B). Accordingly, as pressure reservoir 110 ispressurized by pressure generator 120 (e.g., by depressing piston 121),the new pressure P2 created within pressure reservoir 110 is transmittedto pressure outlet 150B, while the pressure at pressure outlet 150Aremains at the baseline pressure P0.

Note that in various embodiments, diverter 130 can couple pressurereservoir 100 to both pressure outlets 150A and 150B (as shown in FIG.2C) without triggering pressure release valve 140, (e.g., triggeringfeature 132 could be absent from diverter 130). In such embodiments,material delivery system 100 could dispense material individually orsimultaneously from material dispensing elements 155A and 155B.

FIG. 4A shows another embodiment of material delivery system 100(described with respect to FIGS. 1A-1D) in which diverter 130 is asliding element that defines a primary flow path 131A and a secondaryflow path 131B. In particular, diverter 130 is positioned in a passage139 within housing 101, and includes sealing elements 136 (e.g., o-ringsor gaskets) that close passage 139 at various locations. Outlets 150Aand 150B, pressure reservoir outlet 111, optional pressure release valve140, and optional bleed ports 141A and 141B all feed in to passage 139,and are interconnected amongst each other by the particular locations ofsealing elements 136.

For example, in FIG. 4A, flow path 131A connects pressure reservoiroutlet 111 (the pressure reservoir itself is not shown for simplicity,but can be similar to pressure reservoir 110 described with respect toFIGS. 1A-1D and 2A-2F) to pressure outlet 150A, thereby coupling thepressure reservoir to material dispensing element 155A (depicted by aphantom outline for simplicity's sake) to dispense flowable material, asindicated by the solid arrow. A secondary flow path 131B is createdbetween pressure outlet 150B and bleed port 141B, thereby ensuring thatpressure outlet 150B remains at a baseline pressure (e.g., atmosphericpressure) when not actively delivering material from material dispensingelement 155B.

Then, as diverter 130 is moved in the direction indicated by the solidarrow in FIG. 4B, a trigger feature 132 on diverter 130 can actuateoptional pressure release valve 140, thereby venting the pressurereservoir (and hence the pressure supplied to material dispensingelement 155A), as indicated by the dotted arrows. Note that in variousother embodiments, pressure release valve 140 can be eliminated, suchthat the pressure reservoir is not vented when switching outlets,thereby allowing immediate application of pressure to the newly switchedpressure outlet.

Note further that for exemplary purposes, pressure release valve 140 isdepicted as a simple one-way check valve. However, as noted above, invarious other embodiments, pressure release valve 140 can incorporateany pressure release mechanism. Note further that for exemplarypurposes, triggering feature 132 is depicted as a raised element ondiverter 130 that can actuate pressure release valve 140. However, invarious other embodiments, triggering feature 132 can be any system foractuating pressure release valve 140, including a magnetic switch, aproximity sensor, and/or a mechanical linkage.

As switching is completed as shown in FIG. 4C, triggering feature 132allows pressure release valve 140 to close, and the new positions ofsealing elements 136 result in flow path 131A connecting pressurereservoir outlet 111 to pressure outlet 150B, thereby coupling thepressure reservoir to material dispensing element 155B to dispenseflowable material, as indicated by the solid arrow. A secondary flowpath 131C is created between pressure outlet 150A and bleed port 141B,thereby ensuring that pressure outlet 150A remains at a baselinepressure to prevent unintended discharge from material dispensingelement 155A.

FIG. 5A shows another embodiment of material delivery system 100(described with respect to FIGS. 1A-1D) in which diverter 130 is anaxially-rotatable element that defines a first flow path 131A and asecond flow path 131 B. Specifically, diverter 130 a cylindrical elementpositioned within housing 101, with flow paths 131A and 131 B formed aschannels on the surface of the cylinder. The rotational orientation ofdiverter 130, and hence, the positions of flow paths 131A and 131B,determines the particular interconnections between outlets 150A and150B, pressure reservoir outlet 111, and bleed ports 141A and 141B.

For example, in FIG. 5A, flow path 131A connects pressure reservoiroutlet 111 (the pressure reservoir itself is not shown for simplicity)to pressure outlet 150A, thereby coupling the pressure reservoir tomaterial dispensing element 155A (depicted by a phantom outline forsimplicity's sake) to dispense flowable material, as indicated by thesolid arrow. Flow path 131B connects pressure outlet 150B and bleed port141B, thereby ensuring that pressure outlet 150B remains at a baselinepressure (e.g., atmospheric pressure) when not actively deliveringmaterial from material dispensing element 155B.

Then, as diverter 130 is rotated about its longitudinal axis asindicated in FIG. 5B, flow path 131A connects with bleed port 141A(while still connecting pressure reservoir outlet 111 to outlet 150A),thereby venting the pressure reservoir (and hence the pressure suppliedto material dispensing element 155A) to the baseline pressure, asindicated by the dotted arrow.

Continuing to rotate diverter 130 as indicated in FIG. 5C eventuallyresults in flow path 131A being disconnected from pressure reservoiroutlet 111 (although still connecting outlet 150A to bleed port 141A),while flow path 131B disconnects from bleed port 141 B but connectspressure reservoir outlet 111 to outlet 150B. As a result, material canbe dispensed from material dispensing element 155B in response topressure generated within the pressure reservoir, while pressure outlet150A remains at the baseline pressure to prevent unintentional dischargefrom material delivery element 155A.

After desired material dispensing from material delivery element 155B,diverter 130 can be further rotated to cause flow path 131B to connectwith bleed port 141B (while still connecting pressure reservoir outlet111 to outlet 150B), as shown in FIG. 5D. The pressure reservoir (andoutlet 150B at material delivery element 155B) are therefore vented inpreparation for switching output back to material delivery element 155A.Note that while a continuous rotation mode of operation (i.e., rotatingdiverter 130 in a single direction to switch outputs) is described forexemplary purposes, in various other embodiments, output switching canbe performed by rotating diverter 130 between particular angularorientations (i.e., rotating back and forth).

FIGS. 3A-3G show an exemplary use of material delivery system 100 in akyphoplasty procedure. In FIG. 3A, cannulas 310A and 310B are positionedwithin a fractured vertebra 300, thereby providing an access path to thetarget surgical location, which in this case is the cancellous bonestructure 300-C within vertebra 300. Typically, cannulas 310A and 310Bare docked into the exterior wall of vertebral body 300 (using either atranspedicular or extrapedicular approach) using a guide needle and/ordissector, after which a drill or other access tool (not shown) is usedto create a path further into cancellous bone 300-C. However, any othermethod of cannula placement can be used.

Next, cavity-creation tools such as inflatable bone tamps 320A and 320Bare placed into cannulas 310A and 310B, respectively, to positionexpandable members (e.g., balloons) 321A and 321B, respectively, withincancellous bone 300-C. Expandable members 321A and 321B are thenexpanded as shown in FIG. 3B to create cavities 325A and 325B,respectively, within cancellous bone 300-C.

Inflatable bone tamps 320A and 320B are then removed and replaced withmaterial delivery elements 155A and 155B, respectively, coupled tomaterial delivery system 100 (as described with respect to FIGS. 2A-2E)as shown in FIG. 3C. For exemplary purposes, material dispensingelements 155A and 155B are coupled to pressure outlets 150A and 150B,respectively, by flexible hydraulic lines (tubing) 156A and 156B. Thisenables delivery control from a distance, which beneficially allows thephysician to perform the material delivery procedure from outside thefluoroscopic field generated during radioscopic visualization ofvertebral body 300. Note, however, that in various other embodiments,pressure outlets 150A and 150B can be coupled to material dispensingelements 155A and 155B, respectively, by more rigid structures.

For exemplary purposes, material dispensing elements 155A and 155B aredepicted as including storage chambers 157A and 157B, respectively, andlong, thin dispensing outlets (nozzles) 151A and 151B, respectively,that are sized to fit through cannulas 310A and 310B, respectively.Storage chambers 157A and 157B hold an amount of bone filler materialthat can be delivered to cavities 325A and 3256, respectively, viaelongate nozzles 151A and 151 B, respectively.

For exemplary purposes, diverter 130 is initially positioned to couplepressure reservoir 110 to material delivery element 155A. However,diverter 130 can be switched to the opposite position (i.e., couplingpressure reservoir 110 to material delivery element 155B) or can even bein the mid-point position (i.e., coupling pressure reservoir 110 to bothmaterial delivery elements 155A and 155B and opening release valve 140),before switching to a desired one of material delivery elements 155A and155B.

To begin filling cavity 325A, pressure source 120 is used to pressurizepressure reservoir 110, thereby forcing bone filler material 305 frommaterial dispensing element 155A, as shown in FIG. 3D. In the embodimentshown, storage chamber 157A includes a piston 153A that expresses bonefiller material 305 through delivery nozzle 151A and into cavity 325A inresponse to hydraulically-delivered pressure P1 from pressure reservoir110.

Once a sufficient amount of bone filler material 305 is delivered tocavity 325A, diverter 130 can be used to switch the output of materialdelivery system 100. As described with respect to FIGS. 2C and 2D,initiating this switching process as shown in FIG. 3E can open pressurerelease valve 140 (via triggering feature 132) to vent pressurereservoir 110 to the predetermined baseline pressure PO (e.g., ambientpressure). In conjunction, flow path 131 of diverter couples bothmaterial dispensing elements 155A and 1558 to pressure reservoir 110,thereby ensuring that the flow of bone filler material from deliverynozzle 151A is stopped and that no unintended flow of bone fillermaterial occurs from delivery nozzle 151 B.

Upon completion of the switching operation of diverter 130, materialdispensing element 155A is isolated from, and material dispensingelement 1556 is coupled to, pressure reservoir 110, as shown in FIG. 3F.Consequently, as pressure source 120 pressurizes pressure reservoir 110anew, this new pressure P2 only drives bone filler material 305 fromdelivery nozzle 325B of material dispensing element 355B. In thismanner, bone filler material 305 can be delivered to vertebral body 300in a controlled and user-friendly manner.

Note that a sequential two-step bone filler material delivery operation(i.e., fill cavity 325A, and then fill cavity 325B) is described forexemplary purposes only. In various other embodiments, cavities 325A and325B can be filled in any order, using any number of discrete fillingoperations. For example, cavity 325A could be partially filled viamaterial dispensing element 155A, diverter 130 could be used to switchthe output of material delivery system 100 to material dispensingelement 155B to allow partial filling of cavity 325B. Diverter 130 couldthen switch the output back to material dispensing element 155A, toenable additional material delivery to cavity 325A. The filling processcould continue alternating between cavities 325A and 325B until adesired amount of bone filler material 305 is delivered to each.

Once the filling operation is complete, delivery nozzles 151A and 151B,and cannulas 310A and 310B are removed from vertebra 300 (and thepatient's body) as shown in FIG. 3G. Upon hardening, bone fillermaterial 305 provides structural support for vertebra 300, therebysubstantially restoring the structural integrity of the bone and theproper musculoskeletal alignment of the spine. In this manner, the painand attendant side effects of a vertebral compression fracture can beaddressed by the kyphoplasty procedure.

While various embodiments of the invention have been described above, itshould be understood that they have been presented by way of exampleonly, and not limitation. Where methods and steps described aboveindicate certain events occurring in certain order, those of ordinaryskill in the art having the benefit of this disclosure would recognizethat the ordering of certain steps may be modified and that suchmodifications are in accordance with the variations of the invention.Additionally, certain steps may be performed concurrently in a parallelprocess when possible, as well as performed sequentially as describedabove. Thus, the breadth and scope of the invention should not belimited by any of the above-described embodiments, but should be definedonly in accordance with the following claims and their equivalents.While the invention has been particularly shown and described withreference to specific embodiments thereof, it will be understood thatvarious changes in form and details may be made.

The invention claimed is:
 1. A surgical method comprising: providing asingle material delivery system that includes a plurality of outputs, adiverter for selectably coupling a pressure reservoir to one of theplurality of outputs; pressurizing a pressure reservoir to express afirst quantity of bone filler material from a first nozzle into a firsttarget surgical location; decoupling the first nozzle from the pressurereservoir; coupling a second nozzle to the pressure reservoir; andpressurizing the pressure reservoir to express a second quantity of bonefiller material from the second nozzle into a second target surgicallocation, wherein decoupling the first nozzle from the pressurereservoir comprises venting the pressure reservoir to a baselinepressure while the first nozzle remains coupled to the pressurereservoir and then decoupling the first nozzle from the pressurereservoir.
 2. The surgical method of claim 1, wherein venting thepressure reservoir to the baseline pressure comprises opening a pressurerelease valve coupled to the pressure reservoir, and wherein couplingthe second nozzle to the pressure reservoir comprises coupling thesecond nozzle to the pressure reservoir while maintaining the releasevalve in an open condition, and then closing the pressure release valve.3. The surgical method of claim 2, wherein venting the pressurereservoir while the first nozzle remains coupled to the pressurereservoir occurs concurrently with coupling the second nozzle to thepressure reservoir while maintaining the pressure release valve in anopen condition.
 4. The surgical method of claim 3, wherein pressurizinga pressure reservoir to express the first quantity of bone fillermaterial from the first nozzle into the first target surgical locationcomprises: providing a hydraulic fluid in the pressure reservoir;providing a first length of flexible tubing between a first pressureoutlet and a first storage chamber; and positioning a flow path betweenthe pressure reservoir and the first pressure outlet, wherein the firstquantity of bone filler material is expressed from the first storagechamber through the first nozzle in response to the hydraulic fluid flowthrough the first length of flexible tubing.
 5. The surgical method ofclaim 4, wherein pressurizing the pressure reservoir to express thesecond quantity of bone filler material from the second nozzle into thesecond target surgical location comprises: providing a second length offlexible tubing between a second pressure outlet and a second storagechamber; and positioning the flow path between the pressure reservoirand the second pressure outlet, wherein the second quantity of bonefiller material is expressed from the second storage chamber through thesecond nozzle in response to the hydraulic fluid flow through the secondlength of flexible tubing.
 6. The surgical method of claim 5, whereinventing the pressure reservoir while the first nozzle remains coupled tothe pressure reservoir comprises positioning the flow path between thepressure reservoir and the first and second pressure outlets.
 7. Thesurgical method of claim 1, further comprising: decoupling the secondnozzle from the pressure reservoir; re-coupling the first nozzle to thepressure reservoir; and pressurizing the pressure reservoir to express athird quantity of bone filler material from the first nozzle into thefirst target surgical location.
 8. The surgical method of claim 1,further comprising: decoupling the second nozzle from the pressurereservoir; coupling a third nozzle to the pressure reservoir; andpressurizing the pressure reservoir to express a third quantity of bonefiller material from the third nozzle into a third target surgicallocation.
 9. A surgical method comprising: providing a single materialdelivery system that includes a plurality of outputs, a diverterconfigured to simultaneously couple a pressure reservoir to theplurality of outputs; pressurizing a pressure reservoir to express afirst quantity of bone filler material from a first nozzle into a firsttarget surgical location; decoupling the first nozzle from the pressurereservoir; coupling a second nozzle to the pressure reservoir; andpressurizing the pressure reservoir to express a second quantity of bonefiller material from the second nozzle into a second target surgicallocation, wherein decoupling the first nozzle from the pressurereservoir comprises venting the pressure reservoir to a baselinepressure while the first nozzle remains coupled to the pressurereservoir and then decoupling the first nozzle from the pressurereservoir.
 10. The surgical method of claim 9, further comprising:decoupling the second nozzle from the pressure reservoir; coupling athird nozzle to the pressure reservoir; and pressurizing the pressurereservoir to express a third quantity of bone filler material from thethird nozzle into a third target surgical location.
 11. A surgicalmethod comprising: providing a single material delivery system thatincludes first and second outputs, a diverter for selectably coupling apressure reservoir to one of the outputs; moving the diverter to a firstposition to expel a first quantity of bone filler material from thepressure reservoir such that the first quantity of bone filler materialmoves through the first output and into a first target surgicallocation; venting the pressure reservoir to a baseline pressure; andmoving the diverter from the first position to a second position toexpel a second quantity of bone filler material from the pressurereservoir such that the second quantity of bone filler material movesthrough the second output and into a second target surgical location,wherein venting the pressure reservoir occurs after the first quality ofbone filler material moves into the first target surgical location andbefore the second quantity of bone filler material moves into the secondtarget surgical location.
 12. The surgical method of claim 11, whereinventing the pressure reservoir to the baseline pressure occurs while thefirst output is in communication with the pressure reservoir.
 13. Thesurgical method of claim 11, wherein the diverter is moved from thefirst position to the second position while the pressure reservoir hasthe baseline pressure.
 14. The surgical method of claim 11, wherein thefirst output is in communication with the pressure reservoir when thediverter is in the first position and the second output is incommunication with the pressure reservoir when the diverter is in thesecond position.
 15. The surgical method of claim 14, wherein ventingthe pressure reservoir to the baseline pressure occurs while the firstoutput is in communication with the pressure reservoir.
 16. The surgicalmethod of claim 14, wherein the diverter is moved from the firstposition to the second position while the pressure reservoir has thebaseline pressure.
 17. The surgical method of claim 11, wherein ventingthe pressure reservoir to the baseline pressure comprises opening apressure release valve coupled to the pressure reservoir.
 18. Thesurgical method of claim 11, wherein expelling the first and secondquantities of bone filler material from the pressure reservoir comprisespressurizing the pressure reservoir.
 19. The surgical method of claim18, wherein pressurizing the pressure reservoir comprises providing ahydraulic fluid in the pressure reservoir.